Lifetimes of the Metastable D-2 Levels of Calcium Ions Stored in a Paul Ion Trap.

We report a measurement of the lifetime of the $3d{}^{2}{D}_{5/2}$ metastable level in ${}^{40}{\mathrm{Ca}}^{+},$ using quantum jumps of a single cold calcium ion in a linear Paul trap. The $4s{}^{2}{S}_{1/2}--3d{}^{2}{D}_{5/2}$ transition is significant for single-ion optical frequency standards, astrophysical references, and tests of atomic structure calculations. We obtain $\ensuremath{\tau}=1.168\ifmmode\pm\else\textpm\fi{}0.007$ s from observation of nearly $64000$ quantum jumps during $\ensuremath{\sim}32$ h. Our result is more precise and significantly larger than previous measurements. Experiments carried out to quantify systematic effects included a study of a previously unremarked source of systematic error, namely, excitation by the broad background of radiation emitted by a semiconductor diode laser. Combining our result with atomic structure calculations yields $1.20\ifmmode\pm\else\textpm\fi{}0.01$ s for the lifetime of $3d{}^{2}{D}_{3/2}.$ We also use quantum jump observations to demonstrate photon antibunching, and to estimate background pressure and heating rates in the ion trap.We report a measurement of the lifetime of the $3d{}^{2}{D}_{5/2}$ metastable level in ${}^{40}{\mathrm{Ca}}^{+},$ using quantum jumps of a single cold calcium ion in a linear Paul trap. The $4s{}^{2}{S}_{1/2}--3d{}^{2}{D}_{5/2}$ transition is significant for single-ion optical frequency standards, astrophysical references, and tests of atomic structure calculations. We obtain $\ensuremath{\tau}=1.168\ifmmode\pm\else\textpm\fi{}0.007$ s from observation of nearly $64000$ quantum jumps during $\ensuremath{\sim}32$ h. Our result is more precise and significantly larger than previous measurements. Experiments carried out to quantify systematic effects included a study of a previously unremarked source of systematic error, namely, excitation by the broad background of radiation emitted by a semiconductor diode laser. Combining our result with atomic structure calculations yields $1.20\ifmmode\pm\else\textpm\fi{}0.01$ s for the lifetime of $3d{}^{2}{D}_{3/2}.$ We also use quantum jump observations to demonstrate photon antibunching, and to estimate background pressure and heating rates in the ion trap.

arXiv:physics/0002026Physical Review AAug 14, 2000132 citations

Precision spectroscopy with 40 Ca + ions in a Paul trap

Michael Chwalla

Jan 1, 20099 citations

We report a measurement of the lifetime of the

3d{}^{2}{D}_{5/2}

metastable level in

{}^{40}{\mathrm{Ca}}^{+},

using quantum jumps of a single cold calcium ion in a linear Paul trap. The

4s{}^{2}{S}_{1/2}--3d{}^{2}{D}_{5/2}

transition is significant for single-ion optical frequency standards, astrophysical references, and tests of atomic structure calculations. We obtain $\ensuremath{\tau}=1.168\ifmmode\pm\else\textpm\fi{}0.007$ s from observation of nearly

64000

quantum jumps during $\ensuremath{\sim}32$ h. Our result is more precise and significantly larger than previous measurements. Experiments carried out to quantify systematic effects included a study of a previously unremarked source of systematic error, namely, excitation by the broad background of radiation emitted by a semiconductor diode laser. Combining our result with atomic structure calculations yields $1.20\ifmmode\pm\else\textpm\fi{}0.01$ s for the lifetime of

3d{}^{2}{D}_{3/2}.

We also use quantum jump observations to demonstrate photon antibunching, and to estimate background pressure and heating rates in the ion trap.